Mystery of malaria drug resistance solved
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http://www.scidev.net/News/index.cfm?fuseaction=readNews&itemid=1621&language=1
The discovery of how a malaria parasite resists a major anti-
malaria drug could pave the way for a new generation of treat-
ments. (Source: News-Medical.Net)
In a major medical breakthrough, researchers in the United King-
dom and United States have discovered why the malaria parasite
(Plasmodium falciparum) has become resistant to chloroquine, one
of the most effective anti-malarial treatments ever developed.
The research is published today (24 September) in the journal
Molecular Cell.
Researchers at the Liverpool School of Tropical Medicine and the
Albert Einstein College of Medicine, New York, found that a
parasite protein creates a 'back door' out of which drugs can
leak before they can kill the parasite. The researchers believe
the protein could also play a role in the parasite's resistance
to other drugs.
The discovery opens the way for the development of new treat-
ments for malaria, which the World Health Organisation estimates
kills more than one million people a year. The researchers en-
visage a modified version of chloroquine that the parasite's
'back door' protein cannot remove.
Link to full News-Medical.Net news story:
http://www.news-medical.net/?id=5024
Link to abstract of research paper in Molecular Cell 15, 867 (2004):
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WSR-4DCTMKK-
6&_coverDate=09%2F24%2F2004&_alid=203843854&_rdoc=1&_fmt=&_orig=search&_qd=1&_cd
i=7053&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e
0d0e74b78dd64c6f9367b9d76134a0e
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Breakthrough discovery on why the malaria parasite has become
resistant to chloroquine
Scientists at the Liverpool School of Tropical Medicine have
made a major breakthrough in discovering why the malaria para-
site Plasmodium Falciparum, deposited in humans by the mosquito,
has become resistant to chloroquine, one of the most successful
drugs ever used to treat the disease.
Their discovery, described as "a big piece in the jigsaw puzzle"
paves the way for the creation of new drugs to save the lives of
millions of people still infected with malaria every year, many
of them children under five in sub-Saharan Africa.
Once in the body, the malaria parasite multiplies and invades
the red blood cells. A concentration of high levels of chloro-
quine can kill the parasites living in the cells. But the re-
search of Professor Steve Ward and Dr Pat Bray, of the Liverpool
School of Tropical Medicine, working with Dr David Fidock at the
Albert Einstein College of Medicine in New York, has shown how a
protein called PfCRT inside the parasite has enabled it to be-
come resistant to important antimalarial drugs by creating a
'back door' and actually moving the drugs out of the parasite by
leakage. They believe that PfCRT may be a 'master' gene that
controls the parasite's resistance to a variety of antimalarial
drugs.
Malaria death rates have been rising in recent years, partly due
to the parasite's resistance to widely used drugs like chloro-
quine so insights into the resistance mechanism are urgently
needed.